MAP Reading

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Jun 26, 2013 | 01:07 PM

hydro man 17

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From: Hat Creek Ca

MAP Reading

Was just fumbling around with the AE and came up with a MAP value of 26.2-3 at ~ 3500 ft elevation. Is that about correct?
Mike

Jun 26, 2013 | 01:25 PM

01PS

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From: Sandia Park, NM

Looks good from my reference.

Jun 26, 2013 | 04:09 PM

Shake-N-Bake

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From: Mesa AZ

MAP is Manifold Absolute Pressure which is equal to Barometric Pressure plus Boost. If the engine is off and your unit of measure is PSI then you should be reading around 13 ish.

Jun 26, 2013 | 04:40 PM

hydro man 17

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From: Hat Creek Ca

Thanks for the replies. Engine was running at idle.

Jun 26, 2013 | 04:52 PM

Shake-N-Bake

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From: Mesa AZ

Quote:

Originally Posted by hydro man 17

Thanks for the replies. Engine was running at idle.

Then you might see one or two tenths PSI lower than Baro.
This is because there is no boost present at idle but there is a little bit of vacuum in the manifold.

If you are reading 26.3 psi at idle then something is wrong with the sensor or your calibration has modified the look up table for that parameter.

Jun 26, 2013 | 05:00 PM

01PS

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From: Sandia Park, NM

My apologies, I was looking at Baro pressure in In Hg. Shake n Bake is correct, should be 13ish PSI.

Jun 26, 2013 | 05:11 PM

hydro man 17

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From: Hat Creek Ca

I just found a comparison chart and (hopefully) my AE was reading inches of mercury, which at 3500 ft is dead on at 26.3. Truck runs great with no issues other than #6 glow plug problem, which is why I had it hooked up in the first place to check the CEL